1. Technical Field
The present invention relates to a liquid ejecting apparatus and a liquid ejecting method.
2. Related Art
As an example of a liquid ejecting apparatus, a serial-type ink jet printer which performs printing on a medium by ejecting ink as an example of liquid onto the medium while moving an ejecting head in a scanning direction which intersects a transport direction of the medium is known. In such a printer, in a case in which a so-called non-ejecting nozzle (defective nozzle) in which ejection is not performed as intended by the nozzle due to mixing of dust or air bubbles into a nozzle is present, in order to resolve deterioration in image quality due to the non-ejecting nozzle, a non-ejecting complementing control operation, in which complementing is performed by ejecting ink to a region corresponding to a pixel to which the non-ejecting nozzle should eject ink using a substitute nozzle other than the non-ejecting nozzle, is executed.
An ink jet recording apparatus (liquid ejecting apparatus) in JP-A-2005-246840 performs multipass printing in which printing of one raster line is performed by repeating a movement of an ejecting head in a scanning direction, ejecting ink, and transporting a medium by a predetermined distance. In addition, in the liquid ejecting apparatus, when a non-ejecting nozzle is detected in the ejecting head, a plurality of substitute nozzles which perform non-ejecting complementing control are selected, and printing of a pixel which is to be recorded using the non-ejecting nozzle is performed by dispersing the ink in these substitute nozzles.
Meanwhile, in a liquid ejecting apparatus in the related art such as that in JP-A-2005-246840, as illustrated in FIG. 12A, for example, in a case in which a nozzle No. 4 of an ejecting head 200 is detected as a defective nozzle, and a nozzle No. 9 is selected as a substitute nozzle, as illustrated in FIG. 12B, during scanning of the first pass of the ejecting head 200, nozzles No. 1 to 3 and 5, which can eject ink, form dots DT on a medium S (refer to FIG. 12A); however, the nozzle No. 4, which is the defective nozzle, does not form a dot DT on the medium S.
In such a case, in the liquid ejecting apparatus in JP-A-2005-246840, as illustrated in FIG. 13A, in a case in which nozzles No. 6 to 10 form dots DT in a region adjacent to dots DT, which are formed using nozzles No. 1 to 5 on the medium S during scanning of the second pass of the ejecting head 200 after the medium S is transported by a predetermined distance, a dot DT is formed when the nozzle No. 9 ejects ink to a region corresponding to a pixel to which ink is to be ejected using the nozzles No. 4 on the medium S.
However, as illustrated in FIG. 13B, when a position of a medium S with respect to the ejecting head 200 in a transport direction is shifted due to a transport error at a time of scanning of the second pass of the ejecting head 200, the nozzle No. 9 ejects ink to a region on the medium S corresponding to a pixel of the nozzle No. 3, even though the nozzle No. 9 was originally to eject ink to a region on the medium S corresponding to a pixel of the nozzle No. 4. For this reason, an amount of ink of a dot DT formed in the region on the medium S corresponding to the pixel of the nozzle No. 3 increases excessively, and an amount of ink in the region on the medium S corresponding to the pixel of the nozzle No. 4 is zero. As a result, since the difference in the amount of ink between the region on the medium S corresponding to the pixel to which ink is to be ejected using the defective nozzle (nozzle No. 4) and the peripheral region thereof becomes large, there is a concern that image quality may deteriorate.